Delineating the Role of KAP1 in WNT-induced Colorectal Cancer

描述 KAP1 在 WNT 诱导的结直肠癌中的作用

基本信息

批准号：
10358964
负责人：
Ivan D'Orso
金额：
$ 8.2万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-01 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10358964
关键词：
APC gene Adult Basic Science Binding Biochemical Biological Assay Biological Process Cancer Etiology Cell Maintenance Cell Proliferation Cell Survival Cell model Cells Cessation of life ChIP-seq Chromatin Clinic Colon Colonoscopy Colorectal Cancer Complement Factor B Couples DNA biosynthesis Development Disease model Drug Targeting Embryonic Development Epithelial Cells Future Gene Activation Gene Expression Regulation Genes Genetic Transcription Genomics Goals Growth Histones Impairment In Vitro Intestines KRAS2 gene Knockout Mice Knowledge Malignant Neoplasms Measures Metabolic Metabolism Minor Mission Modeling Molecular Normal tissue morphology Oncogenic Pathway interactions Patients Phenotype Physiological Play Property Publishing RNA Polymerase II Reader Regulation Regulator Genes Research Research Proposals Role Series Signal Transduction Small Intestines Specificity Surface TP53 gene Tail Testing Therapeutic WNT Signaling Pathway Work adenoma arm bench to bedside beta catenin biophysical techniques cancer cell cancer initiation cancer therapy cell growth colon cancer patients driver mutation early detection biomarkers genomic RNA improved in vivo insight loss of function mutation mortality mouse model mutant new therapeutic target novel prevent programs promoter reconstitution recruit response restoration small molecule small molecule inhibitor stem cells stemness targeted treatment transcriptome sequencing translational study tumor tumor progression tumorigenesis unpublished works

项目摘要

PROJECT SUMMARY Cell signaling - transcriptional programs play diverse roles in normal development including the regulation of metabolism, cell survival/death, and differentiation, all of which can malfunction in tumorigenesis. The WNT program maintains cell stemness and is highly proliferative, properties that cancer cells hijack to initiate and sustain tumorigenesis. A large body of work has defined that the WNT program is important for both CRC initiation and progression. However, despite previous molecular characterization and identification of small molecules that target the WNT program at multiple levels, a therapeutic arm that successfully inactivates WNT has yet to be employed. Our studies have defined that the transcriptional coregulator KAP1/TRIM28 is required for expression of WNT target genes upon oncogenic WNT activation, suggesting that KAP1 is an alternative drug target in WNT-induced CRC. As such, targeting KAP1 in CRC will require comprehensive characterization of druggable pockets, that if perturbed, would prevent KAP1-dependent oncogenic WNT activation and downstream hallmarks of cancer. Our published studies have identified a mechanism whereby KAP1 uses a previously uncharacterized chromatin reader cassette to directly bind hypoacetylated Histone 4 tails surrounding promoters of non-WNT genes (to facilitate their activation). Our unpublished studies have provided evidence of KAP1 interaction with the pathway- and sequence-specific factor β-Catenin. However, it remains unknown if the chromatin- and β-Catenin–binding activities are critical for KAP1 recruitment to, and for activation of, WNT target genes to support WNT-dependent hallmarks of cancer. Given these findings and critical gaps in knowledge, the central hypothesis of this proposal is that KAP1 uses its chromatin- and β-Catenin–binding functions to activate the oncogenic WNT program to promote CRC transformation and proliferation. As such, the major goal of this research proposal is to explore if KAP1 utilizes these functions to activate WNT target genes, and whether their perturbation would block WNT target gene activation and WNT-induced CRC phenotypes (CRC transformation and cell proliferation). To accomplish this goal, we will leverage the power of genomics (integrated RNA-seq/ChIP-seq approach) and phenotypic assays in established models of CRC tumorigenesis (normal and oncogenic colon epithelial cells). Specifically, we will explore if KAP1 binds WNT target loci upon oncogenic WNT activation in normal colon epithelial cells and whether KAP1 chromatin- and β-Catenin–binding capabilities are required to activate WNT target genes (Aim 1) and to sustain hallmarks of cancer (Aim 2). The basic science research proposed in this “self-contained proposal” will not only reveal fundamental principles of how chromatin readers operate in the context of cancer but also pave the way to identify KAP1 targeting approaches, which is in-line with NCI’s mission to identify novel therapeutic targets to move the discoveries from the bench to the clinics.

项目摘要细胞信号传导 - 转录程序在正常发育中发挥不同的作用，包括调节代谢，细胞存活/死亡和分化，所有这些都可能在肿瘤发生中故障。 wnt 程序维持细胞干并高度增殖，癌细胞劫持的特性启动和维持肿瘤发生。大量工作定义了WNT程序对两个CRC都很重要启动和进展。但是，在先前的分子表征和鉴定之前以多个级别针对Wnt程序的分子，这是一种成功使Wnt失活的治疗臂尚未雇用。我们的研究确定了转录核心节kap1/trim28需要为了表达Wnt靶基因在致癌Wnt激活时，这表明KAP1是一种替代 Wnt诱导的CRC中的药物靶标。因此，CRC中的KAP1靶向将需要全面的特征如果受到干扰，可吸毒的口袋将防止KAP1依赖性致癌wnt激活和癌症的下游标志。我们已发表的研究确定了一种机制，KAP1使用以前未表征的染色质读取器盒直接结合围绕周围的低乙酰化组蛋白4尾巴非Wnt基因的启动子（以促进其激活）。我们未发表的研究提供了证据 KAP1与途径和序列特异性因子β-catenin的相互作用。但是，仍然未知是否染色质和β-catenin结合活性对于KAP1募集至关重要，而对于激活Wnt靶支持Wnt依赖性癌症的基因。鉴于这些发现和知识中的关键差距，该提议的核心假设是KAP1 使用其染色质和β-catenin –结合功能激活致癌Wnt程序以促进CRC 转化和增殖。因此，该研究建议的主要目标是探索KAP1是否使用这些功能激活Wnt靶基因，以及它们的扰动是否会阻止Wnt靶基因激活和WNT诱导的CRC表型（CRC转化和细胞增殖）。实现这一目标目标，我们将利用基因组学的功能（集成的RNA-Seq/CHIP-SEQ方法）和表型测定在既定的CRC肿瘤发生模型（正常和致癌结肠上皮细胞）中。具体来说，我们会的探索Kap1是否在正常结肠上皮细胞中的致癌Wnt激活后结合Wnt靶基因座 KAP1染色质和β-catenin - 结合能力是否需要激活Wnt靶基因（AIM 1）并维持癌症的标志（AIM 2）。这项“独立的基础科学研究建议”不仅会揭示染色质读取者在癌症背景下运作的基本原则而且还为识别KAP1定位方法铺平了道路，这与NCI的任务是识别新颖的使命将发现从长凳转移到诊所的治疗靶标。